Dermographism

Author: Dr Amanda Oakley, Dermatologist, Hamilton, New Zealand,1997.

What is dermographism?

Dermographism is an exaggerated wealing tendency when the skin is stroked. It is the commonest form of physical urticaria. It is also called dermatographism, dermatographia and dermatographic urticaria.

In 25-50% of normal people firm stroking of the skin produces first a white line, then a red line, then slight swelling down the line of the stroke, and a mild red flare in the surrounding skin. In 5% of the population this response is exaggerated enough to be called dermographism. In only a minority of these does it cause any symptoms.

What is the outcome of dermographism?

Dermographism may last for months or go on indefinitely. In many patients, however, it clears within a year or two, or at least the wealing is reduced to a degree which no longer causes significant symptoms.